The invention herein pertains to internal combustion engines and particularly pertains to a method for rebuilding an engine camshaft to provide improved performance and efficiency.
Sanctioned vehicle racing of motor vehicles has become increasingly popular in recent years with higher speeds and technological advances. Engine builders for racing vehicles have sought various ways to improve the performance and fuel efficiency in order to be more competitive. Racing and other engines commonly utilize xe2x80x9cbilletxe2x80x9d type camshafts which are integrally formed such as by conventional machining. Billet type camshafts include cams positioned thereon and at the rear thereof have a distributor drive gear. Once the camshaft has been machined, it is then polished and subjected to high temperature treatments to improve its hardness and durability. Thereafter, the cams are usually ground and finished however, the distributor drive gear is often slightly askew from the longitudinal axis of the camshaft due to the high temperature treatments, although it will engage the distributor drive shaft gear and seemingly, properly operate. Upon close inspection however, the distributor drive gear is slightly out of alignment causing engine performance (cylinder firings) to be somewhat off, resulting in lower power and fuel economy.
Thus, with the problems and disadvantages of conventional distributor drive gears which are integrally formed on billet type camshafts, the present invention was conceived and one of its objectives is to provide a method for rebuilding a billet type camshaft to insure improved engine performance.
It is another objective of the present invention to provide a camshaft which has a distributor drive gear properly aligned on the main shaft and is attached by threaded members.
It is yet another objective of the present invention to provide a method for rebuilding a camshaft which can be readily done by those skilled in the art without extensive training or special equipment.
It is still another objective of the present invention to provide a distributor drive gear which can be substituted for a standard billet distributor drive gear after removal thereof.
Various other objectives and advantages of the present invention will become apparent to those skilled in the art as a more detailed description is set forth below.
The aforesaid and other objectives are realized by first removing the distributor drive gear from a standard billet type camshaft such as by cutting using a conventional lathe. Next in the preferred method, the rear face of the main shaft which has been cut is finished and made true. The face is then drilled to form a bore in the main shaft. A substitute one-part distributor drive gear having a shank extending therefrom is then placed thereon in the preferred embodiment. Machine screws are used to affix the new distributor drive gear to the camshaft and a mounting pin is also employed. In an alternate embodiment for billet camshafts having an interior distributor drive gear, the original distributor drive gear is removed and a new two-part distributor drive gear is affixed to the main camshaft. Thus, with these steps taken the distributor drive gear is now in proper alignment with the longitudinal axis of the camshaft for better engine performance and increased fuel economy.